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A183998 Number of (n+1) X 5 0..2 arrays with all 2 X 2 subblock sums the same. 1
855, 1233, 1887, 3309, 6111, 12525, 26655, 61125, 144495, 361293, 925647, 2471829, 6713631, 18762045, 52968255, 152326725, 440454735, 1288454253, 3779340207, 11166335349, 33034529151, 98175588765, 291944589855, 870672034725 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A184003.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 6*a(n-1) - 60*a(n-3) + 85*a(n-4) + 150*a(n-5) - 360*a(n-6) + 396*a(n-8) - 216*a(n-9).

Empirical g.f.: 3*x*(285 - 1299*x - 1837*x^2 + 14429*x^3 - 4146*x^4 - 47992*x^5 + 37500*x^6 + 49140*x^7 - 48600*x^8) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - 6*x^2)). - Colin Barker, Apr 09 2018

EXAMPLE

Some solutions for 3 X 5:

..2..0..1..0..2....2..1..2..1..0....2..0..1..1..2....1..1..1..2..1

..1..2..2..2..1....0..1..0..1..2....0..2..1..1..0....0..1..0..0..0

..1..1..0..1..1....2..1..2..1..0....1..1..0..2..1....2..0..2..1..2

CROSSREFS

Cf. A184003.

Sequence in context: A185639 A105275 A100969 * A209502 A198527 A234885

Adjacent sequences:  A183995 A183996 A183997 * A183999 A184000 A184001

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 08 2011

STATUS

approved

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Last modified September 27 07:39 EDT 2021. Contains 347672 sequences. (Running on oeis4.)